PINK1 Protects Against Gentamicin-Induced Sensory Hair Cell Damage: Possible Relation to Induction of Autophagy and Inhibition of p53 Signal Pathway

Abstract

Phosphatase and tensin homolog (PTEN)-induced putative kinase 1 (PINK1) is a gatekeeper of mitochondrial quality control. The present study was aimed to examine whether PINK1 possesses a protective function against gentamicin (GM)-induced sensory hair cell (HC) damage in vitro. The formation of parkin particles (a marker revealing the activation of PINK1 pathway which is a substrate of PINK1 and could signal depolarized mitochondria for clearance) and autophagy were determined by immunofluorescence staining. The expressions of PINK1, LC3B, cleaved-caspase 3 and p53 were measured by Western blotting. The levels of reactive oxygen species (ROS) and apoptosis were respectively evaluated by DCFH-DA staining, Annexin V Apoptosis Detection Kit and TUNEL staining. Cell viability was tested by a CCK8 kit. We found that treatment of 400 μM GM elicited the formation of ROS, which, in turn, led to PINK1 degradation, parkin recruitment, autophagy formation, an increase of p53 and cleaved-caspase 3 in HEI-OC1 cells and murine HCs. In contrast, co-treatment with ROS scavenger N-acetyl-L-cysteine (NAC) inhibited parkin recruitment, alleviated autophagy and p53 pathway-related damaged-cell elimination. Moreover, PINK1 interference contributed to a decrease of autophagy but an increase of p53 level in HEI-OC1 cells in response to GM stimulus. Findings from this work indicate that PINK1 alleviates the GM-elicited ototoxicity via induction of autophagy and resistance the increase of p53 in HCs.

LncRNA TUG1 mediates ischemic myocardial injury by targeting miR-132-3p/HDAC3 axis

“…Reactive oxygen species assay. The intracellular ROS assay was performed using 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) staining (D6883, Sigma) as described previously (41). Briefly, cells were stained with 10 M DCFH-DA in serum-free DMEM medium for 30 min and imaged under a fluorescence microscope.…”

Autophagy Regulates the Survival of Hair Cells and Spiral Ganglion Neurons in Cases of Noise, Ototoxic Drug, and Age-Induced Sensorineural Hearing Loss

“…Phosphatase and tensin homolog (PTEN)-induced putative kinase 1 (PINK1) also shown a protective effect against gentamicin and cisplatin-induced ototoxicity. PINK1 promoted autophagy and inhibited the P53 pathway in gentamicin-induced HC damage ( Yang et al, 2018b ), while in response to cisplatin-induced HC and SGN damage, PINK1 induced autophagy and inhibited the JNK signaling pathway ( Yang et al, 2018a ). Peroxiredoxin 1 (PRDX1) also played a protective role in cisplatin-induced SGN damage by activating autophagy through the activation of the PTEN-AKT signaling pathway ( Liu et al, 2021 ).…”

Autophagy: A Novel Horizon for Hair Cell Protection

“…In the tissues with the need of high energy, such as HCs [ 30 ], phosphatase and tensin homolog- (PTEN-) induced putative kinase 1 (PINK1) is highly expressed [ 31 ]. According to a previous study, the suppression of PINK1 and the loss of HEI-OC1 cells were increased, with or without gentamicin (GM) exposure [ 32 ]. In addition, the PINK1 knockdown (KD) cells showed less expression of LC3B but a higher degree of p53 and activated caspase 3, indicating that PINK1 alleviates the GM-induced ototoxicity by inducing autophagy and resisting the level of p53 in HCs [ 32 ].…”